Slide gauge



Aug. 22, 1939. R, wou-ER 2,170,582

SLIDE GAUGE Filed Feb. :5, 1958 fywffz for:

Patented Aug. 22, 1939 UNITED STATES SLIDE GAUGE Robert Wolter, Cologne, Germany Application February 3, 1938, Serial N0. 188,481

In Germany August Z6, 1937 4 Claims.

This invention relates to a slide gauge of the kind comprising a pair of legs one of which is carried by a graduated bar and the other by a slide which is adjustable on said bar.

The degree of accuracy of measurements obtained by gauges of this kind depends to some extent on the pressure with which the slide is urged against the object to be measured, and it has been shown by tests that there can be a considerable variance between measurements taken of the same object by diiierent persons and also by the same person at different times.

The object of the present invention is toprc-vide means in a gauge of this kind which will eliminate the errors due to variations in the pressure applied tol the slide, and the invention consists essentially in the provision on the slide of a spring-controlled thumb piece by which the adjustment of the slide is effected, the thumb piece 'being furnished. with an index which, by cooperation with graduations on the slide, indicates the amount of displacement of the thumb piece in opposition to the spring and thus the degree of pressure applied to the slide.

Fig. 1 of the accompanying drawing represents a side view of a slide gauge constructed according to the invention, and

Fig. 2 is a section on the line A-B of Fig. l.

The gauge consists of a pair of legs la and 2a, one carried by a graduated bar I and the other by a slide 2 which is adjustable along the bar. According to the invention the lower part of the slide is provided with a longitudinal slot wherein a cross bolt 6 is guided. Connected to said bolt between the head anda nut l, is a U-shaped thumb piece 3 which embraces the lower part of the slide and is provided, as shown in Fig'. 1, with a milled, V-shaped lower surface arranged so that it can be conveniently engaged by the thumb I8 for shifting the slide on the bar I. The thumb piece acts on the slide by means of springs I4 and I5 which bear at one end against the bolt 6 through the medium of thrust pieces 8 and 9 and at the other end against abutments I6 and Il which are screwed into bores at the ends of the slide. The springs are guided on rods Ill and Il which pass through the abutments I6 and I'I and are screwed into the thrust pieces 8 and 9. Recesses are made in the abutments I6 and I1 for the accommodation of the screw heads I2 and I3 of the rods. The abutments I6 and Il are adjusted so that an index 4 on the thumb piece 3 will normally be in register with' the central one of three graduations 5 on the slide 2.

From this arrangement it follows that the pressure on the thumb piece 3 in one direction or the other will be transmitted to the slide 2 by means of the springs, the respective thrust piece and guide rod being made to follow the thumb piece in case of relative displacement between 5 it and the slide. If the outer graduations: 5 are chosen as the limit of displacement, and if the thumb piece is always moved into register with these graduations, it is evident that the force exerted on the legs la land 2a will in each case 10 -be constant, so that errors due to irregularity in muscular exertion, will be obviated.

In the case of a gauge which is used exclusively either for Ioutside or inside measurements, `one of the springs may be omitted, and the retained 15 spring may be fastened to the bolt 6.

The device may be modiiied by arranging the spring and guide elements on the outside of the slide instead of within it.

I claim: 20

1. A slide gauge of the character described having a slide, a thumb piece for the adjustment of the slide, said thumb piece being mounted on said slide and movable relatively thereto, resilient means tending to prevent saidthumb piece mov- 25 ing relatively to said slide, and means for indicating the displacement of the thumb piece relative to the slide.

2. A slide gauge of the character described having a slide provided with graduations and with va longitudinal slot, a cross bolt guided in said slot,

a thumb-piece for the adjustment of said slide and connected to said bolt and movable relatively to said slide, an index on the thumb-piece cooperating with said graduations on the slide for indicating the displacement of the thumb-piece relatively to said slide, and resilient means tending to prevent said thumb-piece moving relatively to said slide.

3. A slide gauge of the character described having a slide provided with graduations andl with a longitudinal slot, a cross bolt guided in said slot,

a thumb-piece for the adjustment of said slide connected to said bolt and movable relatively to said slide, an index on the thumb-piece co-operating with said graduations on the slide for indieating the displacement of the thumb-piece relative to said slide, a closure member at each end of the longitudinal slot and a spring between each of said closure members and said cross bolt, said springs tending to prevent said thumb-piece moving' relatively to said slide.

4. A slide-gauge of the character described having a slide provided with graduations and with a longitudinal slot, a cross bolt guided in said slot,

thrust members bearing against said bolt, adjustable screw abutments mounted in the slide at opposite ends of the slot, rods secured to the thrust members and guided in said abutments, a spring on each rod bearing at one end against the adjacent thrust member and at the other end against the abutment, a U-shaped thumbpiece movable relatively to and embracing part of the slide and connected to said bolt for the adjustment of the slide, and an index on the thumb piece co-operating with said graduations on the slide for indicating the displacement of the thumb piece relative to the slide in opposition to the 5 springs.

ROBERT WOLTER. 

